The present invention relates to improvements in railway track support structures and more particularly to improvements in a sleeper or tie collar construction as shown in our U.S. Pat. No. 4,121,766, issued Oct. 24, 1978. That patent, incorporated herein by reference, discloses a track supporting railway tie collar which includes an upper receptacle for loosely receiving an end portion of a cross tie and an enlarged lower bell portion engaged in the ballast beneath the track structure. The rail is supported on a top wall or plate of the upper receptacle and transfers loads directly into the ballast via the bell housing rather than through the tie, thereby greatly prolonging the life of the tie and minimizing track maintenance.
The references cited in U.S. Pat. No. 4,121,766 show various types of solid rail support structures. Other similar railway tie supports are described in U.S. Pat. Nos. 1,425,104 and 1,550,925 and U.S. Ser. No. 224,473, French patent No. 984,858 and German patent No. 77463.
While the tie collar shown in U.S. Pat. No. 4,121,766 has proven to be greatly superior to conventional track structures wherein the train loads are transferred through wooden ties, there is a continuing need to provide improvements in such devices, particularly in terms of strength, load distribution and versatility. A particular concern is the track structure at railway crossings, which has a platform secured over the ties to facilitate the crossing of vehicles. The track structure at such locations is required to carry both vehicle and train traffic. The track cannot be maintained or the ties replaced without removal and subsequent replacement of the platform, which is an expensive and time consuming procedure. Other critical locations are found in switching and track crossing locations, especially those which receive a high degree of traffic and require frequent maintenance.